导　　师： 郑思珣

学科专业： 080502

授予学位： 硕士

作　　者： ;

机构地区： 上海交通大学

摘　　要： 通过简单的方法来制备具有明确链段构成的嵌段共聚物是制备具有综合性能聚合物材料的一条重要的途径。刚性-柔性多嵌段共聚物是一类重要的材料并且根据构成嵌段种类和组成的不同而表现出截然不同的形态和结构。 本论文工作中采用不同分子量的酚羟基封端的聚双酚A羟基醚/(PHOH/)、脂肪胺封端的聚二甲基硅氧烷/(ATPDMS/)及多聚甲醛,通过Mannich缩聚制备了一系列的新型软段-硬段多嵌段共聚物PH-alt-PDMS。聚合反应通过苯并噁嗪环将ATPDMS和PHOH段偶联。差示扫描量热和小角X射线散射均显示该嵌段共聚物为微相分离,嵌段共聚物微相分离的形态是由其两种嵌段PDMS和PHENOXY的不相容引起。通过静态接触角的测试,我们发现对于PH-alt-PDMS,PDMS的引入可以显著提高其疏水性并降低其表面自由能。另外,PH-alt-PDMS交替嵌段共聚物在高温下表现出可自交联性,其自交联的行为由PDMS和聚酚氧链段间的苯并噁嗪环开环导致的。 通过一步法,采用Mannich反应先合成了不同分子量的酚羟基封端的聚苯并噁嗪前驱体,之后进一步与氨基封端聚甲基硅氧烷和多聚甲醛Mannich聚合得到可交联多嵌段共聚物PBDDM-b-PDMS。原子力显微镜和小角X射线散射均显示该嵌段共聚物为微相分离的,其中PDMS以纳米尺度均匀地分散于交联的苯并噁嗪基体中。采用非等温示差扫描量热法/(DSC/)对PBDDM-b-PDMS多嵌段共聚物的交联行为和固化动力学进行了表征,结果表明嵌段共聚物较纯的聚苯并噁嗪前驱体有更高的固化温度及反应活化能,而反应放热焓则明显减少,这是由于软段PDMS的引入造成。热失重分析/(TGA/)被用来研究多嵌段共聚物的热稳定性,通过静态接触角的测试发现,软段PDMS的引入进一步提高了苯并噁嗪基体的疏水性并有效地降低了其表面自由能。 An important strategy for making polymer materials with combined properties is to prepare block copolymers consisting of well-defined blocks via facile approaches. In this thesis, Poly/(hydroxyether of bisphenol A/)-block-polydimethylsiloxane alternating block copolymers /(PH-alt-PDMS/) were synthesized via Mannich polycondensation involving phenolic hydroxyl-terminated poly/(hydroxyether of bisphenol A/), diaminopropyl-terminated polydimethylsiloxane and formaldehyde. The polymerization was carried out via the formation of benzoxazine ring linkages between poly/(hydroxyether of bisphenol A/) and polydimethylsiloxane blocks. Differential scanning calorimetry and small-angle X-ray scattering show that the alternating block copolymers are microphase-separated. Compared to poly/(hydroxyether of bisphenol A/), the copolymers displayed enhanced surface hydrophobicity /(dewettability/). In addition, subsequent crosslinking can occur upon heating the copolymers to elevated temperatures owing to the existence of benzoxazine linkages in the microdomains of hard segments. The subsequent self-crosslinking of the PH-alt-PDMS alternating block copolymers could lead to these polymer materials having potential applications. Poly/(benzoxazine of 4,4’diaminodiphenylmethane/) -b- polydimethylsiloxane multi-block copolymers /(PBDDM-b-PDMS/) were synthesized via the Mannich polycondensation between the phenolic hydroxyls-terminated poly/(h benzoxazine of diaminodiphenylmethane/) with variable molecular weights and diamino-terminated polydimethylsiloxane /(ATPDMS/) by one pot. The micro-separated morphology of the alternating block copolymers was proved by Atomic Force Microscopy and Small Angle X-ray scattering, and the nanodomains of PDMS were dispersed in the crosslinked polybenzoxazine matrix. Non-isothermal differential scanning calorimetry /(DSC/) at different heating rates is used to determine the kinetic parameters of the curing processes of the PBDDM-b-PDMS. Compared to the control polybenzoxazine, the PBDDM-b-PDMS had higher activation energy and less enthalpy of the curing reaction. Thermogravimetric analysis /(TGA/) was applied to evaluate the thermal stability and the surface properties of the copolymer were investigated in terms of the measurement of static contact angle.

关 键 词： 多嵌段共聚物 缩合聚合 交联

分 类 号： [O631.3]

领　　域： [理学] [理学]